Releasing a PDF eBook is Like Writing an iPhone App - and I don't mean that as a compliment!

The unsurpassed guru of mobile phones, Tomi T Ahonen, has released his latest book for free! The book, "The Insider's Guide to Mobile", is an invaluable guide to anyone in the mobile industry. I've read through a few pages of it and it is smart, funny, useful and a hugely important tome for anyone in the industry.

There's just one small niggle I have with it. It is released as a PDF.

PDF is a terrible format for ebooks. Releasing a PDF ebook is the publishing equivalent of releasing an iPhone app. 99% of the time an iPhone app is overkill for what a company is trying to achieve and more often than not completely ignores the target market.

This is something that Tomi has mentioned time and time again on his blog.

Tomi would be better off releasing his book as a mobile website if he wants lots of people to read it on his phone!

I am being slightly unfair on Tomi - but I know that he can take it as well as he dishes it out. He's not a publisher and shouldn't be expected to know every single ebook format out there. But his publishers should.

He and I bother decry the "iPhone first!" mentality - quite rightly. So I am going to educate you on why "PDF First!" doesn't cut the mustard in an ebook world.

Text Reflowing

This is the most important reason. PDFs place hard line breaks at the edge of the page. But what do we mean by "page" on an ebook? Because we can resize text and adjust our margins, the idea of a break at the edge is outdated.

Take this paragraph.

The biggest market for MMS is clearly Asia. As far back as 2008, 48% of Asian mobile phone subscribers were using MMS according to a TNS survey across 29 countries in the Asia-Pacific region.

On a phone or an ereader, the text is likely to render like this:

The biggest market for MMS is clearly Asia. As far back as 2008, 48% of Asian mobile phone subscribers were using MMS according to a TNS survey across 29 countries in the Asia-Pacific region.

The ereader wraps the first line, then it encounters the line break and starts a new line. It does this because it has no way of knowing whether a line break is there because it's the end of the paragraph or the end of the page.

Some ereaders do a better job than others - but even the Kindle isn't immune.

Worse, some phones will not reflow the text at all - meaning you have to scroll right to read a single line, then left all the way, then down all the way. Not the best reading experience in the world. This is how the Kindle - the best eReader on the planet - handles Tomi's PDF.

Fit To Screen View

You can click on the image to see the full resolution version - it's just about readable, even with those large margins (not needed on an ebook!).

What happens if we zoom in?

Zoomed in so it's readable

Much more readable - but we have to scroll left and right to read.

That's the primary reason why PDF sucks. What are the others?

File Size

Let's take a look at a popular free book - Jane Austen's Pride and Prejudice.

Available Formats

Format	Size	Mirror Sites
HTML	719 kB	mirror sites
EPUB	295 kB
Kindle	469 kB
PDF	1.3 MB	mirror sites
Plucker	412 kB
QiOO Mobile	311 kB
Plain Text UTF-8	688 kB
More Files…		mirror sites

The ePub and Kindle formats are zipped - so they are really small. The PDF is twice the size of even the uncompressed plain text version.

Not all of us are lucky enough to live in a world of unlimited download allowances - or even in a land of 3G coverage - and even Kindles have a limit to the amount of memory they have. Making your files as small as possible is a courtesy to your readers.

Security

There are just too many flaws in the PDF reader to make it viable to be installed on handsets or computers. As long as Adobe are continually offering patches, most people would be wise to avoid PDF unless they absolutely need to.

Widespread Adoption

I'll admit, I don't know how many phones have a PDF reader - let alone have a good PDF reader. Whatever the number, I guarantee it to be lower than the number of phones with a web browser.

From Tomi's excellent post on The Year In Stats

100% can do SMS - this is 4.25 Billion phone handsets that can send and receive messages 97% have at least a basic browser (including WAP, not necessarily color) 95% have a color screen - this is 4 Billion, more than twice the number of TV sets and 3x number of PCs 92% are data-capable (at least 2.5G ie GPRS or basic CDMA 2000) 85% support MMS - this is 3.6 Billion, more than twice number of TV sets and 2x active users of eMail 81% are cameraphones - this is 3.4 Billion cameras 76% have a full brower ie HTML type of browser (compare with 17% which is total number of smartphones) 62% have a media player 61% support apps using Java or Brew (compare with 17% which is total number of smartphones) 51% have a memory card slot 35% are 3G phones (not nearly all are on 3G networks) 21% support WiFi 17% are smartphones 12% are second-hand phones (mostly in emerging world countries, but also with younger kids)

No mention of how many phones support PDF! While some modern smartphones like the N95 have a native PDF reader, it's often of low quality and doesn't make for a pleasant reading experience.

Conclusion

I feel really guilty for beating up on Tomi. His book looks wonderful and I'm sure I'll enjoy reading it. I thank him, quite sincerely, for all the advice he dispenses and sanity he injects into the mobile landscape.

He has also been very generous with the terms and conditions of the book. While not explicitly Creative Commons, he does allow the book to be freely copied and quoted - even printed out!

I should also note that in his introduction he says:

Furthermore, if you want a smaller, condensed version optimized for smartphone reading, there is a paid mBook/smartphone version for your iPhone, Blackberry, or whatever pocketable device you might want. The mBook edition also will not be encumbered with the advertising, and will be made in a file size significantly smaller than the free edition, to help those who save the mBook on a smartphone that may have limited storage space. The mBook edition has the illustrations in color to help see some graphics more clearly on the small screen.

In fairness, this book is still in beta - I am confident that Tomi will release a final version which will be accessible to all.

I know he wouldn't give a publisher a free ride if they released an iPhone app where a mobile website would do. I respect him too much to stay silent when I see him releasing a PDF where a more suitable eBook format makes more sense!

I hope he accepts my criticism in the spirit in which it is intended.